The present invention relates to a computer-implemented method for generating a mesh model according to which a two-dimensional mesh model which is efficient in a computer implemented numerical simulation can be easily generated.
In recent years, various computer-implemented numerical simulation methods have been suggested. (see Japanese Patent Application Publication No. 2010-030459 for example)
In order to perform such a numerical simulation, it is necessary to generate a mesh model representing an analysis object.
Heretofore, in order to generate a mesh model, firstly, data about the contour of the analysis object are entered in a computer. Such contour data include data about nodes which can specify the contour of the analysis object. For example, CAD data about the analysis object are used to prepare such contour data.
Next, by the computer, data about additional nodes are added to such contour data, and the space enclosed by the contour of the analysis object is divided into elements (meshing process). Such meshing is automatically performed by the computer, and usually, the density of the nodes in the X-axis direction is the same as that in the Y-axis direction. Namely, the space is automatically, uniformly divided into elements whose aspect ratios are substantially 1.
In the meantime, in a numerical simulation, a physical quantity is computed at the positions of nodes.
From a standpoint of the computational efficiency, it is desirable that the density of the nodes is relatively decreased in a direction in which the gradient of stress in the analysis object is relatively small, in other words, in a direction in which it is acceptable to relatively decrease the analytical accuracy.
on the other hand, in order to increase the analytical accuracy, it is desirable that the density of the nodes is relatively increased in a direction in which the gradient of stress in the analysis object is relatively large, in other words, in a direction in which the analytical accuracy is need to be increased.
Either case results in an element whose aspect ratio is not 1 (one), for example, horizontally long element or vertically long element.
In the case of a two-dimensional mesh model generated by automatic meshing, however, the nodes are defined so that the density of the nodes in the X-axis direction becomes substantially same as that in the Y-axis direction.
Therefore, the number of the elements is liable to increase needlessly.
In such mesh model, if it is desired to arbitrarily define the density of the nodes in a specific direction, it is need to manually change the positions of the nodes automatically, evenly defined by the computer.
Therefore, according to the conventional method for generating a mesh model, it takes much time and labor to create an efficient mesh model of an analysis object.